Your entitled to your opion, however wrong, but you are missing the point.
Are you saying the Zender body kit should only be fitted to genuine Cups? By adding the Zender bodykit(front spoiler, side skirts & 1/4 wings) to a GTV it just looks better IMO, like a Cup.
A pretend M3 doesn't have the M3 engine, the Cup's engine etc etc is the same as a normal V6 so unless sticking a Cup badge on the boot or a plaque on the dash no one is pretending it's a Cup. I've yet to see someone take out their leather seats & fit cloth seats to make the interior look like a Cup.
For advertising purposes adding the word Cup in the title attracts more potential customers but only using the word Cup on its own implies it's a real Cup which ruffled a few anoraks, so I use 'Cup Lookalike' rather than 'Cup body kit' in the title. Most people can then read the full description if interested.
Why people get so 'excited' over the use of the word Cup never fails to amuse me, they're only a red GTV V6 without leather for fecks sake.
They do usually fetch more money though (but not enough to warrant trying to make exact replica copies) as they're very nice & a limited model.